In the audio linked below, you will hear the audio in real time between the tower and the Blackhawk. Although you can't hear the Blackhawk since they are on a differant frequency.
At 15:50 the tower controller tells PAT25 (Blackhawk) there is traffic (Bluestreak 5342) just south of the Widrow Bridge, a CRJ for RWY 33. The controllers transmission ends at 15:56. PAT25 then responds (can't hear this audio, but we know from other sources what PAT25 said). At 16:00 the tower controller then approves the Blackhawk for visual seperation.
In other words it took less than 4 seconds for the Blackhawk crew to locate a plane over 6 miles away and make a radio call saying they have the CRJ in sight and request visual seperation. In my opinion as a private pilot, the male pilot who was the instructor on Blackhawk making the radio calls was complaisant and had made the radio call saying he had the CRJ in sight without ever looking for the CRJ in question or any other plane for that matter, just as he had probally done many times before.
To further complicate things, PAT25 was on a heading of aproximatly 090 degrees when making this call which would have put the CRJ at their 3 oclock. In a helicopter the pilot in command sits in the right seat, the co-pilot sits in the left seat. The male instructor pilot should have been sitting in the left seat, the female pilot in the right seat. In order for the male pilot to see the CRJ he would have needed to look accross the helicotor past the female pilot and out the right side window. Without a cockpit voice recorder we may never know if any of the other two crew members in the helicopter told the male pilot they had the CRJ in sight, but I highly doubt the male pilot could have looked where he needed to look given the position of the helicopter and seen the CRJ in that short of time.
Radar position and track of aircraft at times when radio calls were made can be seen in the video below. Without offical heading information it is hard to determine what the actual heading of the Blackhawk was during the radio call. I'm sure the NTSB will look into this. It seems the data from the accident flight for PAT25 has been deleted from flight tracking systems sites such as Flightaware and Flightradar24.
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